I have several of this lens, and it is SUPERB. It's considered one of Tamron's finest lenses ever. Sharpness rivals primes throughout the range, and I use it as a benchmark against other lenses when testing at 80-200 range. It will equal or beat the SIgma 70-210/2.8 I believe...which is one of the best AF lenses in this range. Robert James - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .